An aggregated file system is typically used for hosting a large number of user files. Each user file includes two distinct portions, user data and metadata. User data is the actual data of a user file that is requested and processed by a client, while metadata is information characterizing the properties and state of the user data, e.g., its location in the file system. When a file switch receives a file open request for the user file, it first retrieves the metadata from a metadata server that is part of the file system. Based on the metadata, the file switch then retrieves different stripes of the user data from one or more storage servers in response to a subsequent file read/write request and applies operations to them accordingly. At the end of the process, the metadata and user data stripes are stored back in their respective hosting metadata server and storage servers.
When a user file includes a large number of user data stripes, this scheme can improve the throughput of the aggregated file system. However, when the user file is small, e.g., including only a single data stripe, this scheme has a serious impact on the performance of the system. One reason is that even in this case the scheme requires at least two round-trip visits, one from the file switch to a metadata server and the other from the file switch to a storage server. Therefore, there is a need for a more efficient scheme for managing small-size user files in an aggregated file system.